In Vitro Engulfment Assay to Measure Phagocytic Activity of Astrocytes Using Synaptosomes
Astrocytes eliminate unnecessary synapses, neural debris, and pathogenic proteins such as amyloid β plaque. Although the emerging evidences suggest that the phagocytic roles of astrocytes are critical in maintaining brain homeostasis during development as well as pathogenic conditions, the efficient assay for measuring phagocytic capacity and kinetics of astrocytes has been lacking. Here we present in vitro engulfment assay using purified astrocytes and synaptosomes. Based on imaging methods, either fluorescent or pH indicator-conjugated synaptosomes can be used in this assay.
Key wordsAstrocytes Phagocytosis Engulfment Degradation pH indicator Synaptosomes Confocal microscope Live imaging
The authors thank all members in Chung’s laboratory for helpful discussion. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (NRF-2016M3C7A1905391,NRF-2016R1C1B3006969, and NRF-2018R1A4A1020922) (W.-S. C).
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